Hundreds of people crowded into King's Cross station today to remember the 52 innocent people killed when four bombs blew themselves up on London’s public transport network three years ago.

Among those marking the third anniversary of 7/7 were survivors of the attacks and relatives of those who died, joined by Boris Johnson, the London Mayor, and Tessa Jowell, the minister responsible for the capital.

They laid flowers outside the station at 8.50am, the time when the first three bombs went off. Mr Johnson laid a memorial card which said: “We honour the memory of those who died on 7/7 2005, we salute the courage of those who were injured and our thoughts and prayers are with all victims and their families.”

The pavements around King’s Cross, from where the four suicide bombers set off on their terror campaign, were crammed with commuters as passers-by stopped to pay their respects.

Relatives of victims and survivors also made personal pilgrimages to the sites of the four blasts - Russell Square, Aldgate and Edgware Road Tube stations, and Tavistock Square.

Daniel Obachike, 34, from Finsbury Park, attended the King’s Cross event to pay tribute to his best friend, Christian Njoya Diawara Small, who died in the blast. He said: “It was a low-key ceremony and there are many of us who believe more could have been done in the aftermath.

“I suppose it is of some consolation that figureheads have arrived to recognise us. I was with Christian the morning before he died - and obviously today feels particularly poignant.”

A small group of family and friends gathered at the entrance to Russell Square station. In a private ceremony, around 20 people observed a minute’s silence at 8.50am Some of them embraced and others held bunches of flowers. Police monitored the group while the morning rush-hour carried on around them.

As tearful families left King’s Cross in the rain, the Rev Kevin McGarhan, who assisted with the rescue efforts three years ago, said that the wounds of grief were "still wide open”.

He said: “Understandably there was a lot of tension today - but it’s so important that we do not allow the terrorists to win. There is a great deal of people, across London and of all faiths, who still feel unsafe, especially in the light of recent stabbings. It just goes to show that we should all put our efforts into supporting the security services.”

Mr McGarhan, 58, has moved to the Church of the Ascension in Ealing, west London, from his former home in Milton Keynes to assist survivors and grieving families. He said: “I first arrived here as a panic-stricken father as I feared for the safety of my daughter but when it emerged she was safe, I stayed on to assist.